var $$ = function(id) {
	return document.getElementById(id);
}
window.onload = function() {
	var btnSelect = $$("btn_select");
	var curSelect = btnSelect.getElementsByTagName("span")[0];
	var oSelect = btnSelect.getElementsByTagName("select")[0];
	var aOption = btnSelect.getElementsByTagName("option");
	oSelect.onchange = function() {
		var text = oSelect.options[oSelect.selectedIndex].text;
		curSelect.innerHTML = text;
	}
}
